:root {
  --bg: #0b1020;
  --text: #e9ecf5;
  --muted: #aab3d6;
  --border: rgba(255,255,255,.14);
  --shadow: 0 10px 25px rgba(0,0,0,.35);
  --radius: 16px;
  --ok: #26d07c;
  --ng: #ff5a7a;
  --accent: #7aa2ff;
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
  --sans: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji","Segoe UI Emoji";
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: var(--sans);
  background: radial-gradient(1200px 800px at 20% 10%, #18244d 0%, var(--bg) 60%);
  color: var(--text);
  line-height: 1.5;
}

header {
  max-width: 980px;
  margin: 28px auto 0;
  padding: 0 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

h1 {
  margin: 0;
  font-size: 20px;
  letter-spacing: .02em;
}

.sub { color: var(--muted); font-size: 13px; margin-top: 6px; }

.wrap {
  max-width: 980px;
  margin: 24px auto 60px;
  padding: 0 16px;
}

.wrap.quiz-layout {
  display: grid;
  grid-template-columns: 1.2fr .8fr;
  gap: 14px;
}

.card {
  background: linear-gradient(180deg, rgba(255,255,255,.06), rgba(255,255,255,.03));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.card .hd {
  padding: 14px 16px;
  border-bottom: 1px solid rgba(255,255,255,.10);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  background: rgba(0,0,0,.15);
  flex-wrap: wrap;
}

.headerRow {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.card .bd { padding: 16px; }

.row {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  align-items: center;
}

.btn {
  appearance: none;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.06);
  color: var(--text);
  border-radius: 12px;
  padding: 10px 12px;
  cursor: pointer;
  transition: transform .03s ease, background .15s ease, border-color .15s ease;
  font-size: 14px;
}

.btn:hover { background: rgba(255,255,255,.10); }
.btn:active { transform: translateY(1px); }
.btn.primary {
  border-color: rgba(122,162,255,.55);
  background: rgba(122,162,255,.18);
}
.btn.danger {
  border-color: rgba(255,90,122,.45);
  background: rgba(255,90,122,.15);
}

.pill {
  font-size: 12px;
  color: var(--muted);
  border: 1px solid var(--border);
  background: rgba(255,255,255,.04);
  padding: 6px 10px;
  border-radius: 999px;
  font-family: var(--mono);
  white-space: nowrap;
}

.small { font-size: 12px; color: var(--muted); }

.filterWrap { margin-bottom: 12px; }
.filterButtons { display: flex; gap: 8px; flex-wrap: wrap; }
.btn.filterBtn.active {
  border-color: rgba(122,162,255,.85);
  background: rgba(122,162,255,.18);
}

.kbd {
  font-family: var(--mono);
  font-size: 12px;
  border: 1px solid rgba(255,255,255,.14);
  border-bottom-color: rgba(255,255,255,.25);
  background: rgba(255,255,255,.05);
  padding: 2px 6px;
  border-radius: 8px;
  color: var(--muted);
}

.tableWrap {
  overflow: auto;
  border: 1px dashed rgba(255,255,255,.18);
  background: rgba(0,0,0,.15);
  border-radius: 14px;
  padding: 0;
}

table.quiz {
  width: 100%;
  min-width: 380px;
  table-layout: fixed;
  border-collapse: separate;
  border-spacing: 18px 10px;
}

table.quiz td {
  border: none;
  padding: 0;
  text-align: center;
  vertical-align: top;
  background: transparent;
}

table.quiz th {
  font-size: 13px;
  font-weight: 700;
  color: var(--muted);
  text-align: center;
  padding: 2px 0;
}

table.stats-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 520px;
}

table.stats-table th,
table.stats-table td {
  font-family: var(--mono);
  font-size: 13px;
  padding: 8px 10px;
  text-align: center;
  border-bottom: 1px solid rgba(255,255,255,.08);
}

table.stats-table th {
  color: var(--muted);
}

table.stats-table td:first-child,
table.stats-table th:first-child {
  text-align: left;
}

.okText {
  color: var(--ok);
}

.ngText {
  color: var(--ng);
}

.hangulCell {
  font-size: 36px;
  padding: 10px 8px;
  border-radius: 14px;
  border: none;
  background: transparent;
  box-shadow: none;
}

.questionCell {
  font-size: 32px;
  padding: 10px 8px;
  border-radius: 14px;
  background: transparent;
}

.question {
  font-size: 36px;
  font-weight: 700;
  letter-spacing: .04em;
  padding: 18px 14px;
  margin-bottom: 16px;
  text-align: center;
  border: 1px solid rgba(255,255,255,.12);
  border-radius: 14px;
  background: rgba(255,255,255,.05);
}

.choices { display: grid; gap: 10px; }
.choice {
  appearance: none;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.06);
  color: var(--text);
  border-radius: 12px;
  padding: 12px 14px;
  cursor: pointer;
  text-align: left;
  font-size: 16px;
  transition: transform .03s ease, background .15s ease, border-color .15s ease;
}
.choice .choice-text {
  font-size: 18px;
}
.choice .hangul-label {
  display: none;
  margin-left: 6px;
  color: var(--muted);
  font-size: 16px;
  font-weight: 600;
}
.choice.revealed .hangul-label { display: inline; }
.choice.correct { border-color: rgba(38,208,124,.75); background: rgba(38,208,124,.16); }
.choice.wrong { border-color: rgba(255,90,122,.75); background: rgba(255,90,122,.14); }
.choice.locked { cursor: default; }
.hint { margin-top: 12px; color: var(--muted); font-size: 13px; }

.quiz-nav {
  margin-top: 16px;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
}
.quiz-nav a {
  font-size: 12px;
  color: var(--muted);
  text-decoration: none;
}
.quiz-nav a:hover,
.quiz-nav a:focus-visible {
  color: var(--text);
}

.kanjiStack {
  display: flex;
  flex-direction: column;
  gap: 8px;
  align-items: stretch;
}

button.cellBtn,
.cellBtn.dummy {
  width: 100%;
  min-width: 0;
  min-height: 48px;
  border: 1px solid rgba(255,255,255,.12);
  background: rgba(0,0,0,.16);
  color: var(--text);
  border-radius: 12px;
  padding: 9px 7px;
  font-size: 22px;
  line-height: 1.25;
  box-sizing: border-box;
  text-align: center;
  white-space: normal;
  overflow-wrap: anywhere;
  word-break: break-word;
}
button.cellBtn { cursor: pointer; }
button.cellBtn:hover { background: rgba(255,255,255,.08); }
button.cellBtn.selected {
  border-color: rgba(122,162,255,.75);
  background: rgba(122,162,255,.16);
}
button.cellBtn.correct {
  border-color: rgba(38,208,124,.75);
  background: rgba(38,208,124,.16);
}
button.cellBtn.wrong {
  border-color: rgba(255,90,122,.75);
  background: rgba(255,90,122,.14);
}
button.cellBtn.active {
  outline: 1px solid rgba(122,162,255,.45);
  outline-offset: -1px;
}
.cellBtn.dummy {
  display: block;
  visibility: visible;
  pointer-events: none;
  color: transparent;
}

.answerPanel {
  margin-top: 12px;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  padding: 0;
  border: 0;
  background: transparent;
  border-radius: 0;
}
.answerPanel .feedback {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.5;
}
.answerPanel .muted {
  color: var(--muted);
  font-size: 12px;
  font-family: var(--mono);
}

.result {
  margin-top: 12px;
  padding: 10px 12px;
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.04);
  font-size: 14px;
  display: none;
}
.result.ok {
  display: block;
  border-color: rgba(38,208,124,.55);
  background: rgba(38,208,124,.12);
}
.result.ng {
  display: block;
  border-color: rgba(255,90,122,.55);
  background: rgba(255,90,122,.15);
}

.popupOverlay {
  position: fixed;
  inset: 0;
  background: rgba(3, 8, 20, .48);
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity .15s ease;
}
.popupOverlay.show {
  display: flex;
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}
.popupCard {
  width: min(92vw, 420px);
  border-radius: 20px;
  padding: 24px 20px;
  box-shadow: var(--shadow);
  border: 1px solid rgba(255,255,255,.16);
  text-align: center;
  color: var(--text);
}
.popupCard.ok {
  background: linear-gradient(135deg, rgba(240,242,245,.96), rgba(222,226,233,.96));
  color: #1f2937;
  border-color: rgba(31,41,55,.12);
}
.popupTitle {
  font-size: 24px;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: .02em;
}
.popupText {
  font-size: 18px;
  margin-bottom: 16px;
  line-height: 1.5;
  word-break: break-word;
}
.popupBtn,
.popupBtn:hover,
.popupBtn:focus-visible,
.popupBtn:active {
  width: 100% !important;
  font-size: 15px !important;
  padding: 12px 14px !important;
  color: #ffffff !important;
  background: #26d07c !important;
  border-color: #26d07c !important;
  box-shadow: none !important;
}
.popupBtn:hover,
.popupBtn:focus-visible,
.popupBtn:active {
  background: #1fb367 !important;
  border-color: #1fb367 !important;
}

textarea {
  width: 100%;
  min-height: 220px;
  border-radius: 14px;
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(0,0,0,.22);
  color: var(--text);
  padding: 12px;
  font-family: var(--mono);
  font-size: 12px;
  box-sizing: border-box;
}

@media (max-width: 860px) {
  .wrap.quiz-layout { grid-template-columns: 1fr; }
  .tableWrap { padding: 0; }
  table.quiz { min-width: 0; border-spacing: 8px 6px; }
  .hangulCell { font-size: 28px; padding: 6px 4px; }
  button.cellBtn,
  .cellBtn.dummy { padding: 8px 6px; min-height: 44px; font-size: 20px; }
}

@media (max-width: 720px) {
  .question { font-size: 28px; }
}

@media (max-width: 520px) {
  .wrap { padding: 0 10px; }
  .card .bd { padding: 8px; }
  .card .hd { padding: 12px; }
  .row { gap: 6px; }
  .btn { padding: 8px 10px; font-size: 13px; }
  .hangulCell { font-size: 24px; padding: 4px 2px; }
  table.quiz { border-spacing: 6px 4px; }
  button.cellBtn,
  .cellBtn.dummy { min-height: 40px; padding: 6px 4px; font-size: 18px; }
  .answerPanel { padding: 10px 12px; }
}